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Journal of Neurotherapy: Investigations in Neuromodulation, Neurofeedback and Applied Neuroscience Limbic Beta Activation and LORETA: Can Hippocampal and Related Limbic Activity Be Recorded and Changes Visualized Using LORETA in an Affective Memory Condition? Rex Cannon BA a , Joel Lubar PhD b , Keri Thornton BA b , Stuart Wilson BA b & Marco Congedo PhD c a experimental psychology program , University of Tennessee, Brain Research and Neuropsychology Lab , Knoxville, TN b University of Tennessee , Knoxville c National Institute for Research in Informatics and Random Systems (IRISA) , France Published online: 08 Sep 2008. To cite this article: Rex Cannon BA , Joel Lubar PhD , Keri Thornton BA , Stuart Wilson BA & Marco Congedo PhD (2004) Limbic Beta Activation and LORETA: Can Hippocampal and Related Limbic Activity Be Recorded and Changes Visualized Using LORETA in an Affective Memory Condition?, Journal of Neurotherapy: Investigations in Neuromodulation, Neurofeedback and Applied Neuroscience, 8:4, 5-24 To link to this article: http://dx.doi.org/10.1300/J184v08n04_02 PLEASE SCROLL DOWN FOR ARTICLE © International Society for Neurofeedback and Research (ISNR), all rights reserved. This article (the “Article”) may be accessed online from ISNR at no charge. The Article may be viewed online, stored in electronic or physical form, or archived for research, teaching, and private study purposes. The Article may be archived in public libraries or university libraries at the direction of said public library or university library. 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SCIENTIFIC ARTICLES Limbic Beta Activation and LORETA: Can Hippocampal and Related Limbic Activity Be Recorded and Changes Visualized Using LORETA in an Affective Memory Condition? Rex Cannon, BA Joel Lubar, PhD Keri Thornton, BA Stuart Wilson, BA Marco Congedo, PhD Rex Cannon is a graduate student working toward a doctoral degree in the experi- mental psychology program at the University of Tennessee, Brain Research and Neuropsychology Lab, Knoxville, TN. Joel Lubar is Professor at the University of Tennessee, Knoxville. Stuart Wilson, and Keri Thornton are students at the University of Tennessee, Knoxville. Marco Congedo is a post-doctoral fellow at the National In- stitute for Research in Informatics and Random Systems (IRISA) in France. Address correspondence to: Rex Cannon, University of Tennessee, Department of Psychology, Brain Research and Neuropsychology Laboratory, Knoxville, TN 37996 (E-mail: [email protected]). The authors give special thanks to Dr. John C. Malone, Dr. Deborah Baldwin, and Jesse Rothove, BA, for sharing their knowledge, time, and editorial assistance. Journal of Neurotherapy, Vol. 8(4) 2004 Copyright © 2004 ISNR. All rights reserved. Digital Object Identifier: 10.1300/J184v08n04_02 5 6 JOURNAL OF NEUROTHERAPY ABSTRACT. Background. The purpose of this study was to determine the validity of Low Resolution Electromagnetic Tomography (LORETA) in visualizing limbic structures and possibly identifying electroenceph- alographic (EEG) frequencies in the limbic region during an anger mem- ory recall process. Method. This study was conducted with twelve subjects, non-clinical students at the University of Tennessee, Knoxville. A pre-study screen- ing was conducted. Eyes-open baselines were obtained employing 300 epochs, or five minutes, using a 19-channel quantitative electroenceph- alographic (qEEG) acquisition system with linked ear reference. The ex- perimental condition recording directly followed an eyes-open baseline. The experimental condition was to allocate a memory that created in- tense anger and retain the state as long as possible. All files were no less than 100 total epochs upon editing. The data were analyzed in both indi- vidual and group conditions with LORETA imaging software. Statisti- cal differences between conditions were evaluated for significance, then computed and transformed into LORETA images. Results. The data revealed significant differences between the anger condition and baseline recordings in limbic structures and frontal regions. The data suggests that limbic lobe and hippocampal activity can be recorded and visualized using LORETA during affective memory recall. There are several notable differences between the baseline and condition images. One of the more interesting of these differences is possible activation of the amygdala, uncinate gyrus and surrounding struc- tures in the beta (12-32 Hz) frequencies. The hemispheric asymmetries dur- ing anger memory recall offer further support for the lateralization of hemispheric activity relating to affective states. Conclusion. LORETA may be an effective method used to differentiate and visualize limbic lobe, hippocampal formation and other related structures during affective anger memory recall. KEYWORDS. LORETA, amygdaloid complex, limbic lobe, hippo- campus, anger, emotional lateralization, mnemonic processes, qEEG, affective cortical processes, mid-brain beta activation INTRODUCTION Research pertaining to the amygdala and hippocampal region is ex- tensive; however, no studies have been conducted on this sub-cortical Scientific Articles 7 area using Low Resolution Electromagnetic Tomography (LORETA) during affective (anger) memory recall. Moreover, studies specific to the amygdala and hippocampus often use external stimuli or a combina- tion of emotional processes rather than focusing on one specific self- generated emotion. The amygdala and hippocampal formation are re- ported to be involved in declarative memory and emotional processes; however, to date activation of either structure in electroencephalo- graphic (EEG) frequencies remains elusive. The purpose of this study was to inquire as to the validity of LORETA in visualizing limbic struc- tures and possibly identifying EEG frequencies in the limbic region dur- ing an affective anger memory process. LORETA (Pascual-Marqui, 1995, 1999, 2000; Pascual-Marqui, Michel, & Lehmann, 1994; Pascual-Marqui, Esslen, Kochi, & Lehmann, 2002a, 2002b) is currently the most accepted inverse solution procedure (Congedo, 2003), and has been widely used in electrophysiological studies (Bosch-Bayard et al., 2001, Isotani et al., 2001; Pizzagalli et al., 2002; Lehmann et al., 2001; Pascual-Marqui et al., 1999) and has been used in numerous laboratories (Fernández-Bouzas et al., 1999; Fuchs, Wagner, Köhler, & Wischmann, 1999; Gomez & Thatcher, 2001; Prichep, John, & Tom, 2001; Worrell et al., 2000). The inverse problem of neurophysiology suggests that electroencephalogram/magnetoen- cephalogram (EEG/MEG) measurements do not provide enough infor- mation for ascertaining the neuronal activity distribution in the volume the brain occupies (Pascual-Marqui et al., 1994). LORETA approxi- mates the distribution of electrical neuronal activity in three-dimen- sional space, basing the approximations on a dense grid of electrodes positioned over the entire scalp (Congedo, 2003). The EEG is a measure of electric potential variations. LORETA estimates the current density that results in a quantifiable potential divergence or the source of the electric field on the scalp (EEG), for which it is feasible to co-register the resolution to a brain atlas (Lancaster et al., 1997, 2000; Talairach & Tournoux, 1988; Towle at al., 1993), and map electrical activity in all cortical structures (Congedo, 2003). LORETA current density is mapped in a space of 2394, 7 ϫ 7 ϫ 7 mm3 voxels. Many of the most recent studies use event-related functional mag- netic resonance imaging (fMRI) techniques and often utilize external stimuli to elicit emotive cortical activity. Damasio et al. (2000) per- formed a positron emission tomography (PET) study on subcortical areas during self-generated emotions, including anger. The results suggest that during self-generated emotional events, limbic and cortical struc- tures that regulate or influence homeostasis are activated. Their study 8 JOURNAL OF NEUROTHERAPY reported activation of the insular and cingulate cortices and limbic areas during these affective mnemonic events, and suggested a region of emo- tion-specific neural patterns that receive or project input to thalamic and other sub-cortical structures. Maratos, Dolan, Morris, Henson, and Rugg (2001) suggest that cortical regions activated by environmental factors are also activated when affective memories are accessed. LORETA methodology has chiefly been exploited to visualize activation in the cortex. Isotani et al. (2001) reported differences between negative, neu- tral and joyful states in the left-posterior regions of the cortex